$\int\left(\frac{t^2-4t+1}{1+t^2}\right)dt$

$\lim_{x\to1}\left(\sqrt{6x+13}\right)$

$\lim_{x\to\infty}\left(\frac{x^a}{b^n}\right)$

$0=\frac{1}{2}e^{\frac{x}{10}}-\frac{1}{2}e^{-\frac{x}{10}}$

$\lim_{x\to\infty}\left(\frac{ln\left(1+\frac{15}{x}\right)}{\frac{1}{x}}\right)$

$\lim_{x\to\infty}\left(\frac{2^x}{\left(ln\left(x\right)\right)^x}\right)$

$\frac{x^4-x^3+4x+1}{x^2+3}$